phil128605

Hey guys, I recently got some problems straightened out on my 99 Rx with the help of some members here and really appreciate it. Now, my RX is occasionally hesitating from a stop. It does it maybe 2 or 3 times every time I drive it. It seems like, if you really ease into the throttle, it will have a hiccup, then accelerate, but if you just gas it and go, it will never do it. Im wondering if it could be the IACV but I searched and it doesnt have any of those symptoms. It idles fine, accelerates great now due to new plugs, and has no other issues except this occasionally hiccup. Any input is appreciated.

Lexmex

I am not sure what you mean by easing into the throttle.

The IACV is one such source of misery there, but another one can be the ABS that can when you come to a stop and are under 5 mph, cause an occasional hiccup.

Do you see any kind of spike in RPM when this happens?

phil128605

No spike in rpm, it just stumbles and wont go. By easing into the throttle, I mean by slowly pressing the pedal down.. But, if I just give it more gas from the start, it wont happen. It only does it from a dead stop.

salimshah

Two things come to mind ..
TPS ...throttle position sensor
Lexmex mod ... adjust slack on the throttle wire.

Salim

hypervish

I want to do the throttle wire mod but don't really understand which bolt to move and which way. Can anybody post a picture after the mod is complete? I just want to see what to move so I don't screw anything up.

Lexmex

https://www.clublexus.com/forums/rx-...se-advise.html see post 5,there's two bolts there and you want to move them as far as left as possible. Start with the bolt furthest to the left.

Lexmex

I'd check to see if you have any exhaust leaks. One area that is prone to them and can cause such a hesitation is here.

hypervish

Thanks Lexmex, I've seen that thread before as well but do you have another picture after the screw is moved. I'm not sure how much to move it.

Lexmex

As far to the left as possible. There's a point it can't go anymore and will come to a stop. I believe the photo above does show it in it's final position as far left as possible.

hypervish

Okay, thanks I will try this later today when I try and locate where the oil is leaking from.

phil128605

check engine light came on today- Codes P1349 and P0300. That is the VVT oil valve on the hard side I believe. I just had this same issue on bank 2 a few months ago, and I removed the OCV and cleaned it with deep creep, and havnt had a problem with it since then. I guess I will try it with this one as well. Is this the correct aproach? By the way, there was no sludge in this engine when I changed the valve cover gaskets this week, and it has 180k. Hard to believe right.

Nad1370

I would'nt say it's the hard side .
Still held by 1 10mm bolt.
Just have to move some vacuum hoses out to get access to it.

My brother had this problem. Same bank.
When I took it out. I shook it and it sounded like there was something loose inside. So I think trying to clean it would'nt work.
He decided to replace it.
If cleaning worked for you on the other side, then by all means try it.

I you do regular oil changes...It's easy to believe you won't have a sludge motor.

salimshah

I myself take lot of advice from Lexmex, but I have slight difference in opinion on how much/little slack on the cable. You should follow what works for you.

The cable loops around the wheel like thing that is the throttle-shaft. You can hold the wheel and spin it [just like if the cable would spin it]. Do this spin action and you can tell how much slack is in the cable. I would say the slack should be at least 1/8" inch.


Salim